src/ap/ieee802_11_auth.c

   1 /*
   2  * hostapd / IEEE 802.11 authentication (ACL)
   3  * Copyright (c) 2003-2009, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  *
  14  * Access control list for IEEE 802.11 authentication can uses statically
  15  * configured ACL from configuration files or an external RADIUS server.
  16  * Results from external RADIUS queries are cached to allow faster
  17  * authentication frame processing.
  18  */
  19
  20 #include "utils/includes.h"
  21
  22 #ifndef CONFIG_NATIVE_WINDOWS
  23
  24 #include "utils/common.h"
  25 #include "utils/eloop.h"
  26 #include "radius/radius.h"
  27 #include "radius/radius_client.h"
  28 #include "hostapd.h"
  29 #include "ap_config.h"
  30 #include "ieee802_11.h"
  31 #include "ieee802_11_auth.h"
  32
  33 #define RADIUS_ACL_TIMEOUT 30
  34
  35
  36 struct hostapd_cached_radius_acl {
  37         time_t timestamp;
  38         macaddr addr;
  39         int accepted; /* HOSTAPD_ACL_* */
  40         struct hostapd_cached_radius_acl *next;
  41         u32 session_timeout;
  42         u32 acct_interim_interval;
  43         int vlan_id;
  44 };
  45
  46
  47 struct hostapd_acl_query_data {
  48         time_t timestamp;
  49         u8 radius_id;
  50         macaddr addr;
  51         u8 *auth_msg; /* IEEE 802.11 authentication frame from station */
  52         size_t auth_msg_len;
  53         struct hostapd_acl_query_data *next;
  54 };
  55
  56
  57 #ifndef CONFIG_NO_RADIUS
  58 static void hostapd_acl_cache_free(struct hostapd_cached_radius_acl *acl_cache)
  59 {
  60         struct hostapd_cached_radius_acl *prev;
  61
  62         while (acl_cache) {
  63                 prev = acl_cache;
  64                 acl_cache = acl_cache->next;
  65                 os_free(prev);
  66         }
  67 }
  68
  69
  70 static int hostapd_acl_cache_get(struct hostapd_data *hapd, const u8 *addr,
  71                                  u32 *session_timeout,
  72                                  u32 *acct_interim_interval, int *vlan_id)
  73 {
  74         struct hostapd_cached_radius_acl *entry;
  75         time_t now;
  76
  77         time(&now);
  78         entry = hapd->acl_cache;
  79
  80         while (entry) {
  81                 if (os_memcmp(entry->addr, addr, ETH_ALEN) == 0) {
  82                         if (now - entry->timestamp > RADIUS_ACL_TIMEOUT)
  83                                 return -1; /* entry has expired */
  84                         if (entry->accepted == HOSTAPD_ACL_ACCEPT_TIMEOUT)
  85                                 if (session_timeout)
  86                                         *session_timeout =
  87                                                 entry->session_timeout;
  88                         if (acct_interim_interval)
  89                                 *acct_interim_interval =
  90                                         entry->acct_interim_interval;
  91                         if (vlan_id)
  92                                 *vlan_id = entry->vlan_id;
  93                         return entry->accepted;
  94                 }
  95
  96                 entry = entry->next;
  97         }
  98
  99         return -1;
 100 }
 101 #endif /* CONFIG_NO_RADIUS */
 102
 103
 104 static void hostapd_acl_query_free(struct hostapd_acl_query_data *query)
 105 {
 106         if (query == NULL)
 107                 return;
 108         os_free(query->auth_msg);
 109         os_free(query);
 110 }
 111
 112
 113 #ifndef CONFIG_NO_RADIUS
 114 static int hostapd_radius_acl_query(struct hostapd_data *hapd, const u8 *addr,
 115                                     struct hostapd_acl_query_data *query)
 116 {
 117         struct radius_msg *msg;
 118         char buf[128];
 119
 120         query->radius_id = radius_client_get_id(hapd->radius);
 121         msg = radius_msg_new(RADIUS_CODE_ACCESS_REQUEST, query->radius_id);
 122         if (msg == NULL)
 123                 return -1;
 124
 125         radius_msg_make_authenticator(msg, addr, ETH_ALEN);
 126
 127         os_snprintf(buf, sizeof(buf), RADIUS_ADDR_FORMAT, MAC2STR(addr));
 128         if (!radius_msg_add_attr(msg, RADIUS_ATTR_USER_NAME, (u8 *) buf,
 129                                  os_strlen(buf))) {
 130                 wpa_printf(MSG_DEBUG, "Could not add User-Name");
 131                 goto fail;
 132         }
 133
 134         if (!radius_msg_add_attr_user_password(
 135                     msg, (u8 *) buf, os_strlen(buf),
 136                     hapd->conf->radius->auth_server->shared_secret,
 137                     hapd->conf->radius->auth_server->shared_secret_len)) {
 138                 wpa_printf(MSG_DEBUG, "Could not add User-Password");
 139                 goto fail;
 140         }
 141
 142         if (hapd->conf->own_ip_addr.af == AF_INET &&
 143             !radius_msg_add_attr(msg, RADIUS_ATTR_NAS_IP_ADDRESS,
 144                                  (u8 *) &hapd->conf->own_ip_addr.u.v4, 4)) {
 145                 wpa_printf(MSG_DEBUG, "Could not add NAS-IP-Address");
 146                 goto fail;
 147         }
 148
 149 #ifdef CONFIG_IPV6
 150         if (hapd->conf->own_ip_addr.af == AF_INET6 &&
 151             !radius_msg_add_attr(msg, RADIUS_ATTR_NAS_IPV6_ADDRESS,
 152                                  (u8 *) &hapd->conf->own_ip_addr.u.v6, 16)) {
 153                 wpa_printf(MSG_DEBUG, "Could not add NAS-IPv6-Address");
 154                 goto fail;
 155         }
 156 #endif /* CONFIG_IPV6 */
 157
 158         if (hapd->conf->nas_identifier &&
 159             !radius_msg_add_attr(msg, RADIUS_ATTR_NAS_IDENTIFIER,
 160                                  (u8 *) hapd->conf->nas_identifier,
 161                                  os_strlen(hapd->conf->nas_identifier))) {
 162                 wpa_printf(MSG_DEBUG, "Could not add NAS-Identifier");
 163                 goto fail;
 164         }
 165
 166         os_snprintf(buf, sizeof(buf), RADIUS_802_1X_ADDR_FORMAT ":%s",
 167                     MAC2STR(hapd->own_addr), hapd->conf->ssid.ssid);
 168         if (!radius_msg_add_attr(msg, RADIUS_ATTR_CALLED_STATION_ID,
 169                                  (u8 *) buf, os_strlen(buf))) {
 170                 wpa_printf(MSG_DEBUG, "Could not add Called-Station-Id");
 171                 goto fail;
 172         }
 173
 174         os_snprintf(buf, sizeof(buf), RADIUS_802_1X_ADDR_FORMAT,
 175                     MAC2STR(addr));
 176         if (!radius_msg_add_attr(msg, RADIUS_ATTR_CALLING_STATION_ID,
 177                                  (u8 *) buf, os_strlen(buf))) {
 178                 wpa_printf(MSG_DEBUG, "Could not add Calling-Station-Id");
 179                 goto fail;
 180         }
 181
 182         if (!radius_msg_add_attr_int32(msg, RADIUS_ATTR_NAS_PORT_TYPE,
 183                                        RADIUS_NAS_PORT_TYPE_IEEE_802_11)) {
 184                 wpa_printf(MSG_DEBUG, "Could not add NAS-Port-Type");
 185                 goto fail;
 186         }
 187
 188         os_snprintf(buf, sizeof(buf), "CONNECT 11Mbps 802.11b");
 189         if (!radius_msg_add_attr(msg, RADIUS_ATTR_CONNECT_INFO,
 190                                  (u8 *) buf, os_strlen(buf))) {
 191                 wpa_printf(MSG_DEBUG, "Could not add Connect-Info");
 192                 goto fail;
 193         }
 194
 195         radius_client_send(hapd->radius, msg, RADIUS_AUTH, addr);
 196         return 0;
 197
 198  fail:
 199         radius_msg_free(msg);
 200         return -1;
 201 }
 202 #endif /* CONFIG_NO_RADIUS */
 203
 204
 205 /**
 206  * hostapd_allowed_address - Check whether a specified STA can be authenticated
 207  * @hapd: hostapd BSS data
 208  * @addr: MAC address of the STA
 209  * @msg: Authentication message
 210  * @len: Length of msg in octets
 211  * @session_timeout: Buffer for returning session timeout (from RADIUS)
 212  * @acct_interim_interval: Buffer for returning account interval (from RADIUS)
 213  * @vlan_id: Buffer for returning VLAN ID
 214  * Returns: HOSTAPD_ACL_ACCEPT, HOSTAPD_ACL_REJECT, or HOSTAPD_ACL_PENDING
 215  */
 216 int hostapd_allowed_address(struct hostapd_data *hapd, const u8 *addr,
 217                             const u8 *msg, size_t len, u32 *session_timeout,
 218                             u32 *acct_interim_interval, int *vlan_id)
 219 {
 220         if (session_timeout)
 221                 *session_timeout = 0;
 222         if (acct_interim_interval)
 223                 *acct_interim_interval = 0;
 224         if (vlan_id)
 225                 *vlan_id = 0;
 226
 227         if (hostapd_maclist_found(hapd->conf->accept_mac,
 228                                   hapd->conf->num_accept_mac, addr, vlan_id))
 229                 return HOSTAPD_ACL_ACCEPT;
 230
 231         if (hostapd_maclist_found(hapd->conf->deny_mac,
 232                                   hapd->conf->num_deny_mac, addr, vlan_id))
 233                 return HOSTAPD_ACL_REJECT;
 234
 235         if (hapd->conf->macaddr_acl == ACCEPT_UNLESS_DENIED)
 236                 return HOSTAPD_ACL_ACCEPT;
 237         if (hapd->conf->macaddr_acl == DENY_UNLESS_ACCEPTED)
 238                 return HOSTAPD_ACL_REJECT;
 239
 240         if (hapd->conf->macaddr_acl == USE_EXTERNAL_RADIUS_AUTH) {
 241 #ifdef CONFIG_NO_RADIUS
 242                 return HOSTAPD_ACL_REJECT;
 243 #else /* CONFIG_NO_RADIUS */
 244                 struct hostapd_acl_query_data *query;
 245
 246                 /* Check whether ACL cache has an entry for this station */
 247                 int res = hostapd_acl_cache_get(hapd, addr, session_timeout,
 248                                                 acct_interim_interval,
 249                                                 vlan_id);
 250                 if (res == HOSTAPD_ACL_ACCEPT ||
 251                     res == HOSTAPD_ACL_ACCEPT_TIMEOUT)
 252                         return res;
 253                 if (res == HOSTAPD_ACL_REJECT)
 254                         return HOSTAPD_ACL_REJECT;
 255
 256                 query = hapd->acl_queries;
 257                 while (query) {
 258                         if (os_memcmp(query->addr, addr, ETH_ALEN) == 0) {
 259                                 /* pending query in RADIUS retransmit queue;
 260                                  * do not generate a new one */
 261                                 return HOSTAPD_ACL_PENDING;
 262                         }
 263                         query = query->next;
 264                 }
 265
 266                 if (!hapd->conf->radius->auth_server)
 267                         return HOSTAPD_ACL_REJECT;
 268
 269                 /* No entry in the cache - query external RADIUS server */
 270                 query = os_zalloc(sizeof(*query));
 271                 if (query == NULL) {
 272                         wpa_printf(MSG_ERROR, "malloc for query data failed");
 273                         return HOSTAPD_ACL_REJECT;
 274                 }
 275                 time(&query->timestamp);
 276                 os_memcpy(query->addr, addr, ETH_ALEN);
 277                 if (hostapd_radius_acl_query(hapd, addr, query)) {
 278                         wpa_printf(MSG_DEBUG, "Failed to send Access-Request "
 279                                    "for ACL query.");
 280                         hostapd_acl_query_free(query);
 281                         return HOSTAPD_ACL_REJECT;
 282                 }
 283
 284                 query->auth_msg = os_malloc(len);
 285                 if (query->auth_msg == NULL) {
 286                         wpa_printf(MSG_ERROR, "Failed to allocate memory for "
 287                                    "auth frame.");
 288                         hostapd_acl_query_free(query);
 289                         return HOSTAPD_ACL_REJECT;
 290                 }
 291                 os_memcpy(query->auth_msg, msg, len);
 292                 query->auth_msg_len = len;
 293                 query->next = hapd->acl_queries;
 294                 hapd->acl_queries = query;
 295
 296                 /* Queued data will be processed in hostapd_acl_recv_radius()
 297                  * when RADIUS server replies to the sent Access-Request. */
 298                 return HOSTAPD_ACL_PENDING;
 299 #endif /* CONFIG_NO_RADIUS */
 300         }
 301
 302         return HOSTAPD_ACL_REJECT;
 303 }
 304
 305
 306 #ifndef CONFIG_NO_RADIUS
 307 static void hostapd_acl_expire_cache(struct hostapd_data *hapd, time_t now)
 308 {
 309         struct hostapd_cached_radius_acl *prev, *entry, *tmp;
 310
 311         prev = NULL;
 312         entry = hapd->acl_cache;
 313
 314         while (entry) {
 315                 if (now - entry->timestamp > RADIUS_ACL_TIMEOUT) {
 316                         wpa_printf(MSG_DEBUG, "Cached ACL entry for " MACSTR
 317                                    " has expired.", MAC2STR(entry->addr));
 318                         if (prev)
 319                                 prev->next = entry->next;
 320                         else
 321                                 hapd->acl_cache = entry->next;
 322 #ifdef CONFIG_DRIVER_RADIUS_ACL
 323                         hapd->drv.set_radius_acl_expire(hapd, entry->addr);
 324 #endif /* CONFIG_DRIVER_RADIUS_ACL */
 325                         tmp = entry;
 326                         entry = entry->next;
 327                         os_free(tmp);
 328                         continue;
 329                 }
 330
 331                 prev = entry;
 332                 entry = entry->next;
 333         }
 334 }
 335
 336
 337 static void hostapd_acl_expire_queries(struct hostapd_data *hapd, time_t now)
 338 {
 339         struct hostapd_acl_query_data *prev, *entry, *tmp;
 340
 341         prev = NULL;
 342         entry = hapd->acl_queries;
 343
 344         while (entry) {
 345                 if (now - entry->timestamp > RADIUS_ACL_TIMEOUT) {
 346                         wpa_printf(MSG_DEBUG, "ACL query for " MACSTR
 347                                    " has expired.", MAC2STR(entry->addr));
 348                         if (prev)
 349                                 prev->next = entry->next;
 350                         else
 351                                 hapd->acl_queries = entry->next;
 352
 353                         tmp = entry;
 354                         entry = entry->next;
 355                         hostapd_acl_query_free(tmp);
 356                         continue;
 357                 }
 358
 359                 prev = entry;
 360                 entry = entry->next;
 361         }
 362 }
 363
 364
 365 /**
 366  * hostapd_acl_expire - ACL cache expiration callback
 367  * @eloop_ctx: struct hostapd_data *
 368  * @timeout_ctx: Not used
 369  */
 370 static void hostapd_acl_expire(void *eloop_ctx, void *timeout_ctx)
 371 {
 372         struct hostapd_data *hapd = eloop_ctx;
 373         time_t now;
 374
 375         time(&now);
 376         hostapd_acl_expire_cache(hapd, now);
 377         hostapd_acl_expire_queries(hapd, now);
 378
 379         eloop_register_timeout(10, 0, hostapd_acl_expire, hapd, NULL);
 380 }
 381
 382
 383 /**
 384  * hostapd_acl_recv_radius - Process incoming RADIUS Authentication messages
 385  * @msg: RADIUS response message
 386  * @req: RADIUS request message
 387  * @shared_secret: RADIUS shared secret
 388  * @shared_secret_len: Length of shared_secret in octets
 389  * @data: Context data (struct hostapd_data *)
 390  * Returns: RADIUS_RX_PROCESSED if RADIUS message was a reply to ACL query (and
 391  * was processed here) or RADIUS_RX_UNKNOWN if not.
 392  */
 393 static RadiusRxResult
 394 hostapd_acl_recv_radius(struct radius_msg *msg, struct radius_msg *req,
 395                         const u8 *shared_secret, size_t shared_secret_len,
 396                         void *data)
 397 {
 398         struct hostapd_data *hapd = data;
 399         struct hostapd_acl_query_data *query, *prev;
 400         struct hostapd_cached_radius_acl *cache;
 401         struct radius_hdr *hdr = radius_msg_get_hdr(msg);
 402
 403         query = hapd->acl_queries;
 404         prev = NULL;
 405         while (query) {
 406                 if (query->radius_id == hdr->identifier)
 407                         break;
 408                 prev = query;
 409                 query = query->next;
 410         }
 411         if (query == NULL)
 412                 return RADIUS_RX_UNKNOWN;
 413
 414         wpa_printf(MSG_DEBUG, "Found matching Access-Request for RADIUS "
 415                    "message (id=%d)", query->radius_id);
 416
 417         if (radius_msg_verify(msg, shared_secret, shared_secret_len, req, 0)) {
 418                 wpa_printf(MSG_INFO, "Incoming RADIUS packet did not have "
 419                            "correct authenticator - dropped\n");
 420                 return RADIUS_RX_INVALID_AUTHENTICATOR;
 421         }
 422
 423         if (hdr->code != RADIUS_CODE_ACCESS_ACCEPT &&
 424             hdr->code != RADIUS_CODE_ACCESS_REJECT) {
 425                 wpa_printf(MSG_DEBUG, "Unknown RADIUS message code %d to ACL "
 426                            "query", hdr->code);
 427                 return RADIUS_RX_UNKNOWN;
 428         }
 429
 430         /* Insert Accept/Reject info into ACL cache */
 431         cache = os_zalloc(sizeof(*cache));
 432         if (cache == NULL) {
 433                 wpa_printf(MSG_DEBUG, "Failed to add ACL cache entry");
 434                 goto done;
 435         }
 436         time(&cache->timestamp);
 437         os_memcpy(cache->addr, query->addr, sizeof(cache->addr));
 438         if (hdr->code == RADIUS_CODE_ACCESS_ACCEPT) {
 439                 if (radius_msg_get_attr_int32(msg, RADIUS_ATTR_SESSION_TIMEOUT,
 440                                               &cache->session_timeout) == 0)
 441                         cache->accepted = HOSTAPD_ACL_ACCEPT_TIMEOUT;
 442                 else
 443                         cache->accepted = HOSTAPD_ACL_ACCEPT;
 444
 445                 if (radius_msg_get_attr_int32(
 446                             msg, RADIUS_ATTR_ACCT_INTERIM_INTERVAL,
 447                             &cache->acct_interim_interval) == 0 &&
 448                     cache->acct_interim_interval < 60) {
 449                         wpa_printf(MSG_DEBUG, "Ignored too small "
 450                                    "Acct-Interim-Interval %d for STA " MACSTR,
 451                                    cache->acct_interim_interval,
 452                                    MAC2STR(query->addr));
 453                         cache->acct_interim_interval = 0;
 454                 }
 455
 456                 cache->vlan_id = radius_msg_get_vlanid(msg);
 457         } else
 458                 cache->accepted = HOSTAPD_ACL_REJECT;
 459         cache->next = hapd->acl_cache;
 460         hapd->acl_cache = cache;
 461
 462 #ifdef CONFIG_DRIVER_RADIUS_ACL
 463         hapd->drv.set_radius_acl_auth(hapd, query->addr, cache->accepted,
 464                                       cache->session_timeout);
 465 #else /* CONFIG_DRIVER_RADIUS_ACL */
 466 #ifdef NEED_AP_MLME
 467         /* Re-send original authentication frame for 802.11 processing */
 468         wpa_printf(MSG_DEBUG, "Re-sending authentication frame after "
 469                    "successful RADIUS ACL query");
 470         ieee802_11_mgmt(hapd, query->auth_msg, query->auth_msg_len, NULL);
 471 #endif /* NEED_AP_MLME */
 472 #endif /* CONFIG_DRIVER_RADIUS_ACL */
 473
 474  done:
 475         if (prev == NULL)
 476                 hapd->acl_queries = query->next;
 477         else
 478                 prev->next = query->next;
 479
 480         hostapd_acl_query_free(query);
 481
 482         return RADIUS_RX_PROCESSED;
 483 }
 484 #endif /* CONFIG_NO_RADIUS */
 485
 486
 487 /**
 488  * hostapd_acl_init: Initialize IEEE 802.11 ACL
 489  * @hapd: hostapd BSS data
 490  * Returns: 0 on success, -1 on failure
 491  */
 492 int hostapd_acl_init(struct hostapd_data *hapd)
 493 {
 494 #ifndef CONFIG_NO_RADIUS
 495         if (radius_client_register(hapd->radius, RADIUS_AUTH,
 496                                    hostapd_acl_recv_radius, hapd))
 497                 return -1;
 498
 499         eloop_register_timeout(10, 0, hostapd_acl_expire, hapd, NULL);
 500 #endif /* CONFIG_NO_RADIUS */
 501
 502         return 0;
 503 }
 504
 505
 506 /**
 507  * hostapd_acl_deinit - Deinitialize IEEE 802.11 ACL
 508  * @hapd: hostapd BSS data
 509  */
 510 void hostapd_acl_deinit(struct hostapd_data *hapd)
 511 {
 512         struct hostapd_acl_query_data *query, *prev;
 513
 514 #ifndef CONFIG_NO_RADIUS
 515         eloop_cancel_timeout(hostapd_acl_expire, hapd, NULL);
 516
 517         hostapd_acl_cache_free(hapd->acl_cache);
 518 #endif /* CONFIG_NO_RADIUS */
 519
 520         query = hapd->acl_queries;
 521         while (query) {
 522                 prev = query;
 523                 query = query->next;
 524                 hostapd_acl_query_free(prev);
 525         }
 526 }
 527
 528 #endif /* CONFIG_NATIVE_WINDOWS */